Environmental monitoring systems can be used in a number of circumstances. Accidents involving radiological cargo, unplanned discharges of contaminants to liquid or air, analysis of radiological storage systems, and remediation and decommission of contaminated buildings and areas all may involve analysis of the environment in and around a location of interest. With off-site laboratory analysis, it may take up to 6 weeks to ship acquired samples to a laboratory and receive results. In this time, conditions may shift leading to potential danger or further contamination. As well, if it turns out that the contamination is minimal or non-extant, significant and avoidable delays may be incurred.
In such cases, on-site analysis of environmental materials may be preferable. On-site analysis may minimize or prevent time delays in determining the potential dangers and environmental impact.
For example, mercuric (Hg) nitrate is used as a catalyst in the medical isotope production process to ensure consistent Mo-99 target dissolution. The subsequent high level radiological liquid waste is cemented into stainless steel pails and shipped to waste management areas for long term storage. The liquid waste may be stored in concrete tile holes. These tile holes are often engineered concrete structures surrounded by compacted soil and shielded with a concrete plug.
At current Mo-99 production rates, approximately 10 kg/yr of Hg in cemented waste is placed in storage. Structural degradation of Portland cement is often expected to occur in 7-20 years (after placement in tile hole), resulting in increased surface area and higher leaching rates. While the bulk of the stored Hg has been found to be strongly incorporated in the cement (˜80%), there is potential for leaching of the Hg into the surrounding environment. As a result, it may be desirable to have a system to evaluate the potential for and magnitude of Hg releases during storage.
A portable detection apparatus may be desired to alleviate some of the above-noted concerns. As well, a compact and portable detection apparatus capable of analyzing and modelling a variety of contaminants released in fluid form may provide flexibility to monitor different environmental situations.